ℓ-torsion bounds for the class group of number fields with an ℓ-group as Galois group

Klüners, Jürgen; Wang, Jiuya

doi:10.1090/proc/15882

$\ell$-torsion bounds for the class group of number fields with an $\ell$-group as Galois group
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by Jürgen Klüners and Jiuya Wang PDF

Proc. Amer. Math. Soc. 150 (2022), 2793-2805

Abstract:

We describe the relations among the $\ell$-torsion conjecture, a conjecture of Malle giving an upper bound for the number of extensions, and the discriminant multiplicity conjecture. We prove that the latter two conjectures are equivalent in some sense. Altogether, the three conjectures are equivalent for the class of solvable groups. We then prove the $\ell$-torsion conjecture for $\ell$-groups and the other two conjectures for nilpotent groups.

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